Vertically reciprocating perforated agitator

Abstract

The present invention comprises a horizontal, perforated agitator element and means to cause the agitator element to reciprocate vertically within a reservoir containing a fluid suspension, solution, or mixture. The perforations in the agitator element are sized and located so that an array of pipette tips may be inserted into the fluid through the moving agitator element without interference.

We claim:  
     
       1. A device for agitating fluids, comprising: 
       (a) an agitator element of substantially lamellar form, disposed substantially horizontally within a fluid inside a container, having holes therein, said holes disposed in an array substantially matching a fixed array of pipette tips and shaped and sized so that said pipette tips may be moved through said holes in said agitator element without said pipette tips and said agitator element physically contacting one another;  
       (b) means for intermittently moving said agitator element from a first position to a second position in a substantially vertical direction; and  
       (c) means for returning said agitator element from said second position to said first position in a substantially vertical direction.  
     
     
       2. The device claimed in claim  1  wherein said agitator element comprises a magnetic attraction portion and wherein said moving means comprises an electromagnet, said electromagnet intermittently energized to attract said magnetic attraction portion and move said agitator element from said first position to said second position. 
     
     
       3. The device claimed in claim  2  wherein said returning means comprise a biasing means that causes said agitator element to return to said first position when said electromagnet is de-energized. 
     
     
       4. The device claimed in claim  3  wherein said biasing means comprises one or more mechanical springs. 
     
     
       5. The device claimed in claim  3  wherein said agitator element is buoyant within said fluid and said biasing means comprises flotation of said agitator element within said fluid. 
     
     
       6. The device claimed in claim  1  wherein said agitator element comprises a permanent magnet portion and said moving means and said returning means comprise an electromagnet energized by a current which intermittently alternates its direction, thereby alternatively attracting and repulsing said permanent magnet portion and causing said agitator element to reciprocate. 
     
     
       7. The device claimed in claim  1  wherein said moving and returning means comprise a reciprocating machine directly attached to said agitator element. 
     
     
       8. A method for simultaneously agitating and pipetting fluids, comprising: 
       (a) providing an agitator element of substantially lamellar form, disposed substantially horizontally within a fluid inside a container, having holes therein, said holes disposed in an array substantially matching a fixed array of pipette tips and shaped and sized so that said pipette tips may be moved through said holes in said agitator element without said pipette tips and said agitator element physically contacting one another;  
       (b) reciprocating said agitator element in a substantially vertical direction;  
       (c) vertically inserting said pipette tips into said fluid such that said pipette tips and said agitator element do not contact one another;  
       (d) pipetting into and/or out of said fluid using said pipette tips; and  
       (e) vertically withdrawing said pipette tips from said fluid.